Link is gone, but you still can follow the above link. I downloaded everything (client, clusterware, etc) but only the database downloadlink results in a stubborn 404.

System requirements for 11g are in an order of a magnitude that I wonder why Oracle even bothers to ship 32-bit versions. And I even have a 64-bit machine AT HOME! Now guess what ALL of our servers are.

Checking operating system requirements …
Check complete. The overall result of this check is: Not executed
OUI-15038: Unable to execute rule ‘CertifiedVersions’ from ruleset ‘OSChecks’. The underlying test ‘oracle.sysman.oip.oipc.oipcz.OipczOSChecks.checkCertifiedOSVersions’ has thrown an unhandled exception [For input string: “18446744073709551615”]. If the exception results in a failure of the test and the exception needs to be propagated, then encapsulate the exception in the result object and return the result.
Recommendation: Make sure you are installing the software on the correct platform.
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